Methods of using an adjustable variable stiffness medical device

ABSTRACT

A transluminal device may include an elongate section extending between a proximal end and a distal end of the device. The elongate section may be configured to be inserted into a body cavity. The device may include a balloon within the elongate section between the proximal end and the distal end.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/590,790, filed Aug. 21, 2012, which is based upon and claims thebenefit of priority under 35 U.S.C. §119(e) of U.S. ProvisionalApplication No. 61/526,359 to Kappel et al. filed on Aug. 23, 2011, theentirety of both of which are incorporated herein by reference.

FIELD OF THE INVENTION

Embodiments of the present invention relate to a transluminal devicewith an adjustable variable stiffness flexible shaft. In particular,exemplary embodiments of the present invention relate to endoscopes,catheters and other transluminal devices that are inserted into a body.Embodiments of the present invention also cover methods of using suchdevices.

BACKGROUND OF THE INVENTION

A transluminal device is a flexible instrument introduced into the bodyfor diagnostic or therapeutic purposes. These devices are inserted intothe body through a natural or an artificially created opening, and aredelivered to a work site inside the body through a body channel, suchas, for example, the esophagus, a blood vessel, etc. Examples oftransluminal devices include endoscopes, catheters, etc. Although theinvention may be broadly applied to any transluminal device, for thesake of brevity and as an exemplary embodiment, the invention will bedescribed as being applied to an endoscope in this disclosure.

Endoscopes are widely used for diagnostic and therapeutic purposesinside a body. There are many different uses for endoscopes, andtypically, endoscope designs may be varied to optimize their performancefor an intended application. For example, there are upper endoscopes forexamination of the esophagus, stomach and duodenum, urethroscopes forexamining the urethra and bladder, colonoscopes for examining the colon,angioscopes for examining the blood vessels and heart, bronchoscopes forexamining the bronchi, laparoscopes for examining the peritoneal cavity,arthroscopes for examining joint spaces, etc. Each of these devices mayinclude features to optimize their performance for the intendedapplication.

In typical applications, a distal end of an endoscope is inserted intothe body through a natural anatomic opening, such as, for example, themouth, anus, vagina, etc. Endoscopes may also be inserted into the bodythrough an incision created for the purpose. The distal end of theendoscope then proceeds from the point of insertion to a region ofinterest (work site) within the body by traversing a body channel. Theendoscope may also include one or more lumens configured to delivervarious diagnostic or treatment devices to the work site within thebody. These diagnostic or treatment devices may include, among others, alight source, a viewing device, an irrigation lumen, an aspirationlumen, a temperature sensor, a heating probe, an ultrasonic sensor, alaser catheter or the like. These and other devices that may be usedwith an endoscope are broadly referred to as therapeutic or diagnostictools in this application. Therapeutic tools configured for specifictherapeutic tasks (such as, for example, incision, grasping, stitching,etc.) may also be delivered to the work site through the lumens of theendoscope.

To minimize patient discomfort, the diameter of an endoscope may bemaintained at a size below the size of the body channel through whichthe endoscope passes. This size restriction may limit the number andsize of the lumens in the endoscope. To minimize patient discomfort,endoscopes must also be sufficiently flexible to permit the distal endof the endoscope to follow the body cavity as the distal end progressestoward the work site. For example, as the endoscope traverses thehepatic flexure region of the digestive track, increased flexibility maybe desirable. While greater endoscope flexibility may enable theendoscope to traverse tortuous body channels, it may be desirable toincrease the stiffness of selected regions of the endoscope for improvedmaneuverability. For instance, when traversing the transverse colonregion of the digestive track, increasing the stiffness of selectedregions of the endoscope may be advantageous. Varying the stiffness ofselected regions of the endoscope may also prevent kinking of the lumenspassing therethrough.

SUMMARY OF THE INVENTION

An embodiment of the invention may include a transluminal device. Thetransluminal device may include an elongate section extending between aproximal end and a distal end of the device. The elongate section may beconfigured to be inserted into a body cavity. The device may include aballoon within the elongate section between the proximal end and thedistal end.

Various embodiments of the invention may include one or more of thefollowing aspects: a flexibility of the elongate section may beconfigured to decrease when the balloon is inflated, and the flexibilitymay be configured to increase when the balloon is deflated; the balloonmay extend substantially from the proximal end to the distal end of theelongate section; a length of the balloon may be substantially smallerthan a length of the elongate section; the balloon may include multipleindependently inflatable segments; some segments of the multiplesegments may be configured to inflate and deflate independently of othersegments; the balloon may be fixed in the device; the device may includea lumen extending within the elongate section from the proximal end tothe distal end, and the balloon may be positioned within the lumen andconfigured to be axially movable between the proximal end and the distalend; the device may be an endoscope; the balloon may have a semicircularcross-sectional shape.

Another embodiment of the invention may include a method of using atransluminal device. The method may include inserting a distal end ofthe device into a body cavity. The device may include a lumen extendingfrom a proximal end of the device to the distal end. The method may alsoinclude positioning a balloon at a first location within the lumen, thefirst location being a location between the proximal end and the distalend, and moving the balloon from the first location to a second locationin the lumen between the proximal end and the distal end. The method mayalso include inflating the balloon by admitting a fluid therein.

Various embodiments of the invention may include one or more of thefollowing aspects: the method may further include inserting the ballooninto the lumen; the step of inflating the balloon may be performed afterpositioning the balloon at the first location; the step of inflating theballoon may be performed before positioning the balloon at the firstlocation; the method may further include deflating the balloon byremoving the fluid therefrom; deflating the balloon may increase aflexibility of the device; inflating the balloon may include inflating afirst section of the balloon independent of a second section of theballoon by admitting fluid into the first section while not admittingfluid into the second section, the first section and the second sectionsbeing different sections of the balloon; and inflating the balloondecreases a flexibility of the device.

Another embodiment of the invention may include a transluminal device.The device may include an elongate section extending between a proximalend and a distal end of the device. The elongate section may include afirst region and a second region between the proximal end and the distalend. The device may also include a balloon. The balloon may beconfigured to increase a flexibility of the first region. The inflatableballoon may also be configured to increase the flexibility of the secondregion independently of increasing the flexibility of the first region.

Various embodiments of the invention may include one or more of thefollowing aspects: the balloon may be configured to radially expand froma deflated configuration to an inflated configuration by admitting afluid therein; the flexibility of the first region may be configured toincrease from a first value corresponding to the deflated condition ofthe balloon to a second value corresponding to the inflated condition ofthe balloon; the device may also include a lumen extending within theelongate section from the proximal end to the distal end; the balloonmay be disposed within the lumen; the balloon may be movable from thefirst region to the second region; the balloon may extend substantiallyfrom the proximal end to the distal end of the elongate section; alength of the balloon may be substantially smaller than a length of theelongate section; the balloon may include multiple segments that areconfigured to inflate and deflate separated by sections that do notsubstantially inflate and deflate when the fluid is admitted into orremoved from the balloon; some segments of the multiple segments may beconfigured to inflate and deflate independently of other segments; theballoon may be fixed in the device; and the device may further include awire configured to move the balloon between the first region and thesecond region.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments of the invention andtogether with the description, serve to explain the principles of theinvention.

FIG. 1 is a schematic view of an embodiment of an endoscope with anadjustable variable stiffness flexible shaft performing an exemplaryendoscopic surgery.

FIG. 2 is an illustration of the distal end of the endoscope of FIG. 1.

FIG. 3A-3C are illustrations of three different embodiments of theinflatable balloon of the endoscope of FIG. 1.

FIG. 4 is an illustration of a method of using an embodiment of thecurrent invention.

DESCRIPTION OF THE EMBODIMENTS

Reference will now be made to exemplary embodiments of the invention,examples of which are illustrated in the accompanying drawings. Whereverpossible, the same reference numbers will be used throughout thedrawings to refer to the same or like parts.

FIG. 1 depicts an exemplary endoscope 10 performing an exemplaryendoscopic surgery. In the embodiment depicted in FIG. 1, the endoscope10 may be inserted into the stomach 100 through the esophagus. Theendoscope 10 may be positioned at a location proximate to a stomach wall18 where a therapeutic procedure may be performed (“work site”). Thework site 28 could include, for instance, a tear 16 on stomach wall 18.It should be emphasized that the illustrated application of theendoscope 10 in FIG. 1 is exemplary only, and that the endoscopes of thecurrent disclosure may be applied to any endoscopic application known inthe art.

The endoscope 10 may include a flexible elongate member 12 extendingbetween a proximal end 20 and a distal end 30. In the configurationdepicted in FIG. 1, the proximal end 20 may include the end of theendoscope 10 external to the body and the distal end 30 may include theend of the endoscope 10 internal to the body. Proximal end 20 mayinclude actuation devices or other control mechanisms (not shown) thatmay be used to operate endoscope 10. For instance, these controlmechanisms may allow an operator to move (translate, rotate, etc.)distal end 30 of endoscope 10 to position the distal end 30 in apreferred orientation to perform a desired therapeutic task. Theflexibility of elongate member 12 may enable endoscope 10 to bend andpass through tortuous body passages as distal end 30 advances to worksite 28. The endoscope 10 may be constructed of a plurality of materialssome or all of which may be biocompatible. Typically, a part of theendoscope 10 that contacts the internal surfaces of a body may be madesubstantially of a biocompatible material.

The endoscope 10 may include a plurality of lumens 14 runninglongitudinally therethrough. Each lumen 14 may extend between theproximal end 20 external to the body and the distal end 30 internal tothe body. In some embodiments, a longitudinal axis of the lumens may besubstantially parallel to a longitudinal axis 26 of the endoscope 10. Insome embodiments, lumens 14 may be formed integrally with endoscope 10,while in other embodiments lumens 14 may resemble small hollow tubes (orcatheters) through a longitudinal cavity of endoscope 10. The lumens 14may have any size and shape. In some embodiments, different lumensincluded in endoscope 10 may have different sizes and/or shapes. In someembodiments, some of lumens 14 may be dedicated for a particular taskwhile other lumens may be hollow cavities, or working lumens, throughwhich a desired therapeutic or diagnostic tool 50 may be delivered towork site 28. Some of lumens 14 dedicated for a particular task mayinclude an irrigation lumen, an aspiration lumen, an illumination lumen,and a viewing lumen.

The irrigation lumen may be configured to deliver a fluid (such as, forexample, a cleaning fluid) to work site 28. Irrigation lumen, therefore,may be configured to facilitate fluid flow therethrough. In someembodiments, proximal end 20 of the irrigation lumen may be configuredto be attached to a source of fluid. In some embodiments, distal end 30of the irrigation lumen may have devices (such as nozzles) configured toalter the flow of fluid exiting the lumen.

The aspiration lumen may be configured to remove fluid from work site28. Aspiration lumen may, therefore, be configured to facilitate suctionand/or fluid flow. In some embodiments, the flow of fluid through theaspiration lumen and the irrigation lumen may be in substantiallyopposite directions. For example, fluid may flow through an irrigationlumen towards the distal end 30, while fluid flow through the aspirationlumen may be towards the proximal end 20. Fluid flow through anirrigation lumen and an aspiration lumen may be independently operated,or their operation may be coordinated to perform a function, such as theextraction of a tissue sample from work site 28. In these embodiments,fluid may be delivered to work site 28 through the irrigation lumen, anda tissue sample may be removed from work site 28 through the aspirationlumen along with the fluid. The proximal end 20 of the aspirationchannel may also be configured to be attached to a source of suctionand/or a container configured, for example, to collect the tissuesamples.

The viewing lumen may include devices configured to display a visualimage of work site 28 external to the body. These devices may includeimaging means (such as lens for a CCD, CMOS, or other camera) at distalend 30 and cables (electrical and/or optical cables) configured totransmit a recorded image to a display device external to the body. Theillumination lumen may include devices configured to illuminate worksite 28. These devices may include illumination devices (such as bulbsand/or other solid state light emitting devices) at distal end 30 andcables (such as fiber optic cables and/or light guides) configured todeliver power and other signals (such as, instructions) to theseillumination devices. In some embodiments, viewing and illuminationlumens may include a lens and/or other devices that facilitateillumination and viewing of work site 28.

The working lumens may include a hollow cavity that extend from proximalend 20 to distal end 30 of endoscope 10. These lumens 14 may beconfigured to deliver a therapeutic tool or diagnostic 50 to work site28. A distal end of the therapeutic tool 50 may be inserted into a lumen14 and pushed down the length of elongate section 12 to extend an endeffector 22 at work site 28. One or more therapeutic or diagnostic tools50 may be delivered to work site 28 through lumen 14.

Some or all of these lumens 14 may have a substantially circularcross-section. However, it is also contemplated that they may have anysuitable shape, size, and/or configuration. For instance, in someembodiments, the shape of the lumen 14 may be specially tailored to passan end effector 22 without a corresponding increase in diameter ofendoscope 10.

Therapeutic tool 50 may include a shaft 24 that connects the endeffector 22 to an actuation device (not shown) external to the body. Theactuation device may be configured to operate the end effector 22.Operation of the end effector 22 may include performing a desiredtherapeutic task at work site 28. The end effector 22 may include anymedical instrument configured to perform the desired therapeutic task atthe work site 28. Non-limiting examples of end effectors 32 may includebiopsy forceps, baskets, graspers, snares, surgical knives, needles,suturing instruments, heating elements for cauterizing instruments, alaser lithotripter, etc. In some embodiments, the actuation device mayalso be configured to move (that is, translate, rotate, etc.) the endeffector 22 at work site 28. The actuation device may be attached toproximal end 20 of endoscope 10 and may be part of a larger controlmechanism or it may be a separate control mechanism.

Endoscope 10 may also include an inflatable balloon 40 passingtherethrough. Inflatable balloon 40 may be any device that may radiallyexpand (inflate) when filled with a fluid, and radially contract whenthe fluid is removed. In addition to radial expansion, inflation of someembodiments of inflatable balloon 40 may also include longitudinalexpansion. FIG. 2 shows an illustration of an embodiment of distal end30 of endoscope 10. It should be emphasized that the structure of theendoscope illustrated in FIG. 2 is exemplary only, and in general, theinventive concepts of the current application may be applied to anyendoscope known in the art. In the illustration of FIG. 2, some externalparts of endoscope 10 have been removed to illustrate parts within. Asdescribed earlier, multiple lumens 14 may extend from proximal end 20 ofendoscope 10 to distal end 30. Some of these lumens 14 may be dedicatedfor a particular task while other lumens may be hollow cavities, orworking lumens, through which a desired therapeutic tool 50 may bedelivered to work site 28. An inflatable balloon 40 may also extend todistal end 30 alongside lumens 14. Although inflatable balloon 40 isdepicted as a relatively large semicircular segment in the embodimentillustrated in FIG. 2, inflatable balloon 40 may possess any shape andsize. In some embodiments, the shape and size of inflatable balloon 40may be tailored to optimize the use of available space within endoscope10.

In some embodiments, balloon 40 may include a taper at one or both ofits proximal and distal ends. The tapered end of the balloon 40 may helpin moving the balloon through the lumen. In some embodiments, balloon 40may include reinforcing features such as webbing in the walls or thesurface to increase a stiffness and/or the strength of the balloon 40 inselected regions. In some embodiments, balloon 40 may include internalstylets, support catheters or the like to assist in advancing theballoon 40 through a lumen. In some embodiments, the wall thickness ofthe material may be selected based on a desired strength or rigidity ofthe balloon 40. In some embodiments, balloon 40 may include filamentloops or other connectors to assist in retracting the balloon 40 or tomove the balloon 40 from one location to another.

In some embodiments, inflatable balloon 40 may extend through a lumen 14of endoscope 10 while in other embodiments, inflatable balloon 40 may beembedded in endoscope 10. In embedded embodiments, inflatable balloon 40may be built-in anywhere in endoscope 10. In embodiments whereinflatable balloon 40 extends through lumen 14, inflatable balloon 40may extend through any lumen 14 of endoscope 10. The balloon 40 may alsohave a shape to match the shape of the lumen. In these embodiments,inflatable balloon 40 may be an accessory that an operator may insertinto lumen 14 and inflate as desired. Inflatable balloon 40 may also bepre-fixed in a lumen. In such an embodiment, an operator may insert alumen with an inflatable balloon 40 pre-attached to it, into endoscope10. Inflatable balloon 40 may include an expandable sheath 42 enclosinga cavity. Sheath 42 may be constructed from any biocompatible material,including elastomeric, rubber, or other materials which permitsinflatable balloon 40 to be radially flexible. Non-limiting examples ofballoon 40 materials may include materials such as polyethyleneterephthalate (PET) and Nylon. Inflatable balloon 40 may be configuredto inflate and deflate as desired to selectively vary the flexibility ofendoscope 10. In some embodiments, the sheath 42 of balloon 40 may havea low compliance to support the endoscope without overexpansion. Ingeneral, the balloon 40 may have any cross-sectional shape and length.For example, in some embodiments, balloon 40 may have a cross-sectionalshape that is circular, semi-circular, oval, elliptical, or anothercurved shape. In some embodiments, the cross-sectional shape of balloon40 may resemble the segment of a circle. It is also contemplated that,in some embodiments, the shape of balloon 40 may resemble an annularring or a segment of an annular ring.

Inflation of inflatable balloon 40 may be accomplished by filling thesheath 42 with a fluid. Any fluid, such as air, water or a liquid, maybe used to fill inflatable balloon 40. Deflating inflatable balloon 40may be accomplished by draining the fluid from sheath 42. In thedeflated configuration, endoscope 10 may be highly flexible. That is,elongate member 12 of endoscope 10 may flex or bend relatively easily.This flexibility of elongate member 12 may assist endoscope 10 tonavigate around curved or winding body cavities as it advances towardswork site 28. In the inflated configuration, the flexural rigidity(“rigidity”) of the portion of endoscope 10 that include inflatableballoon 40 increases. That is, the flexibility of elongate member 12decreases. Controlling the amount of fluid in inflatable balloon 40 mayvary the flexibility of endoscope 10 between low flexibility (that is,high rigidity) in a fully inflated configuration to high flexibility(that is, low rigidity) in a fully deflated configuration.

Inflatable balloon 40 may be fluidly coupled to a fluid (air, water,liquid, etc.) source at proximal end 20 of endoscope 10. The fluidsource may include any reservoir of the fluid such as, for example, atank of air, a needle or other reservoir of fluid, etc. Proximal end ofendoscope 10 may also include a control mechanism (or other activationmeans) that may be used to inflate and deflate inflatable balloon 40.The control mechanism may include, but not limited to, pumps (manual,electric, etc.), storage reservoirs (tanks, etc.), valves (mechanical,electric, electronic, etc.), computer controls, etc. In someembodiments, the control mechanism may include programmable logic thatenables the inflatable balloon 40 to be inflated to suit a particularregion of the body. The control mechanism may be included along withother controls of endoscope 10, or it may be a stand alone controlmechanism. In one embodiment, the control mechanism may be operated topump fluid from the fluid source to inflatable balloon 40 to increasethe rigidity of endoscope 10. The control mechanism may also be operatedto drain fluid from inflatable balloon 40 to deflate inflatable balloon40, and thereby, increase the flexibility of endoscope 10.

Inflatable balloon 40 may provide the ability to control the flexibilityof endoscope 10 during a therapeutic procedure. In some instances it maybe desirable to change the flexibility of an endoscope during aprocedure. For example, as endoscope 10 is inserted into the human body,a sufficiently stiff distal end 30 may permit endoscope 10 to be pushedinto the body cavity. During insertion, a stiff distal end 30 mayprevent endoscope 10 from bending on itself or kinking when being pushedinto a tight body cavity or lumen. When distal end 30 traverses througha bend in body cavity to reach work site 28, it may be desirable tosufficiently decrease the stiffness of endoscope 10 to allow distal end30 to navigate the bend without damaging body tissue. Once distal end 30reaches work site 28, for some therapeutic tasks, it may be desirable tomake the distal end 30 more rigid or more flexible to perform themedical procedure.

Endoscope 10, which encloses lumens 14 and inflatable balloon 40, may beconstructed by any means known in the art. In some embodiments, multiplelumens 14 and inflatable balloon 40 may be enclosed by a winding 44.Winding 44 may be made of any material, such as a metal, an elastomeric,a plastic, a fabric, or a rubber material. Winding 44 may have the formof a thin strip of material wrapped around lumens 14 and inflatableballoon 40. This structure of the winding 44 may enable endoscope 10 tobe flexible. Winding 44 may be covered by an inner cover 46 and an outercover 46. Inner cover 46 and/or outer cover 48 may comprise water proofmaterial that prevents biological fluids from seeping into endoscope 10.Inner cover 46 and/or outer cover 48 may also be made of flexiblebiocompatible materials. The external surface of outer cover 48 may besufficiently lubricious so that endoscope 10 may traverse body cavitieswithout patient discomfort. Although FIG. 2 illustrates an embodiment ofendoscope 10 with winding 44 wrapped by inner cover 46 and outer cover48, it should be emphasized that this illustration is exemplary only,and endoscope 10 may have any structure known in the art. For instance,in some embodiments, endoscope 10 may only include a cover whichencloses lumens 14. In some embodiments, it may desirable to reduce theradial expansion of endoscope 10 as inflatable balloon 40 is inflated.In these embodiments, the number and/or the material of these covers maybe chosen to prevent the radial expansion of endoscope 10.

Balloon 40 may have any length. In some embodiments, the length of theballoon 40 may be selected to match the length of a body tract. Forinstance, in some embodiments, the length of balloon 40 mayapproximately match a length of flexible section of a body tract. Insome embodiments, balloon 40 may be a continuous length balloon thatextends substantially the entire length (from proximal end 20 to distalend 30) of endoscope 10. In other embodiments, balloon 40 may have alength smaller than the length of endoscope 10. FIGS. 3A-3C illustratethree embodiments of inflatable balloons that may be used with endoscope10. In the embodiment of FIG. 3A, inflatable balloon 40A extendssubstantially the entire length of endoscope 10. In such an embodiment,inflation of inflatable balloon may increase the rigidity of the entirelength of endoscope 10. Such an embodiment of inflatable balloon 40A maybe desirable for some therapeutic procedures where increasing thestiffness of the entire endoscope may make the procedure easier.

Inflatable balloon 40A may be embedded or fixed in endoscope 10 or itmay extend through a lumen 14. In an embodiment where inflatable balloon40A may be embedded, it may be built-in anywhere on endoscope, such as,for example, between winding 44 and inner cover 46 of FIG. 2. In anembodiment where inflatable balloon 40A extends through a lumen 14,inflatable balloon 40A may be removed and inserted into lumen 14 asdesired. For embodiments where inflatable balloon 40 is a continuouslength balloon, selectively reducing the stiffness of a region ofendoscope 10 may include removing the inflatable balloon 40 from thatsection of endoscope 10. Removing inflatable balloon 40 from a sectionof endoscope 10 may include pulling (or pushing) inflatable balloon 40away from that section of endoscope 10. For instance, to reduce thestiffness of distal end 30 of endoscope 10, inflatable balloon 40 may beremoved from the distal end 30 by pulling a section of inflatableballoon 40 out of lumen 14 from proximal end 20.

FIG. 3B illustrates an embodiment where the length of inflatable balloon40B may be smaller than the length of endoscope 10. In such anembodiment, the location of inflatable balloon 40B along the length ofendoscope 10 may be fixed or it may be movable along the length ofendoscope 10. In embodiments where the location of inflatable balloon40B may be fixed, inflatable balloon 40 may be fixed at a location whereit may be desirable to vary endoscope flexibility. In such an embodimentinflatable balloon 40B may be embedded in endoscope 10 or it may befixed within lumen 14. In an embodiment where the location of inflatableballoon 40B may be varied, inflatable balloon 40B may travel withinlumen 14. In such an embodiment, wires, links or other mechanismsattached to inflatable balloon 40B may extend to proximal end 20 ofendoscope 10. Pulling or pushing these wires or links may moveinflatable balloon 40B along the length of lumen 14. These wires, links,or other mechanisms may allow inflatable balloon 40B to be pulled intoposition at a location where a change in endoscope flexibility isdesired. Inflatable balloon 40B may have any length up to the length ofendoscope 10. In some embodiments, inflatable balloon 40B may be smalland extend only a small length of endoscope 10, while in otherembodiments inflatable balloon 40B may be longer.

Inflatable balloon 40B may be used for therapeutic or diagnosticprocedures where it may be desirable to vary the stiffness of selectedlengths of endoscope 10. For instance, in a colonoscopic procedure, whenthe tip of the endoscope is advanced halfway up the cecum, it may behelpful for the portion of the endoscope at the anal verge to berelatively rigid and inflexible, while the portion beyond the anal vergemay need to be relatively flexible. In such an application, selectedregions of the endoscope may be made flexible or rigid by positioningand inflating inflatable balloon 40B at the desired location, as theendoscope is advanced through the colon.

FIG. 3C illustrates another embodiment of inflatable balloon which maybe used to vary the flexibility of endoscope 10. In the embodiment ofFIG. 3C, inflatable balloon 40C may include a series of segmentedballoons extending from proximal end 20 to distal end 30. Inflatableballoon 40C of this embodiment may include multiple balloon segments oflength 52C separated by a non-inflatable section 54. The length of eachsegment may be the same or it may be different. In an inflatedconfiguration, the non-inflatable sections 54 may be regions of reducedstiffness that may allow endoscope 10 to flex about these regions. Insome embodiments of inflatable balloon 40C, the balloon may extendsubstantially the entire length of endoscope 10. In other embodiments,inflatable balloon 40C may have a smaller length. In some embodiments,ducts or access ports passing through non-inflatable sections mayconnect individual balloon segments so that fluid may pass between thesesegments. In other embodiments, individual balloon segments of theinflatable balloon 40C may be inflated individually. In such anembodiment, selected balloon segments may be inflated and selectedballoon segments deflated to vary the stiffness of different regions ofendoscope 10.

Inflatable balloon 40C may be embedded in endoscope 10 or it may bepulled to a desired position as in the embodiment of FIG. 3B. In such anembodiment, as in the embodiment of FIG. 3B, links or other mechanismsattached to inflatable balloon 40C may allow inflatable balloon 40C tobe pulled into position at a location where a change in endoscopeflexibility is desired. Other embodiments of inflatable balloon mayinclude a combination of continuous sections and segments which may bepulled into a desired location as needed.

FIG. 4 illustrates a method of using endoscope 10 with an adjustablevariable stiffness flexible shaft. Endoscope 10 first may be prepared tobe inserted into a body cavity (step 110). In some embodiments, thisstep may include cleaning the endoscope and/or inserting desired devices(such as, for example, illumination and viewing devices) into lumens 14of endoscope 10. In some embodiments, this step may include inserting aninflatable balloon 40 into a lumen 14 of endoscope 10 and fluidlycoupling inflatable balloon 40 to a fluid reservoir. As indicatedearlier, in some embodiments, inserting an inflatable balloon into lumen14 of endoscope 10 may include inserting a lumen with a pre-attachedinflatable balloon into endoscope 10. In some embodiments, theinflatable balloon 40 may also be coupled to a link of sufficient lengththat will extend out of the proximal end of lumen 14 when inflatableballoon 40 is inserted into the lumen. In an embodiment where inflatableballoon 40 is embedded in the endoscope, step 110 may include couplinginflatable balloon 40 to the fluid reservoir.

The inflatable balloon 40 at the distal end of endoscope 10 may beinflated in step 120. In some embodiments, this step may also includepositioning inflatable balloon 40 at a desired location (such as, forinstance at the distal end 30 of endoscope 10). Positioning inflatableballoon 40 at a desired location may be accomplished by pushing/pullinga link coupled to inflatable balloon 40. In some embodiments, a lumenwith an inflatable balloon 40 disposed within it is pulled/pushed toposition inflatable balloon 40 at a desired location. Inflatable balloon40 may be positioned at a desired location before or after it isinflated. That is, inflatable balloon 40 may be positioned at a desiredlocation before being inflated, or the inflatable balloon 40 may beinflated first before being positioned a desired location. Inflatinginflatable balloon 40 at a desired location may increase the stiffnessof that location of endoscope 10. In some applications, inflatableballoon 40 may be inflated at distal end 30 of endoscope 10 toselectively increase the stiffness of the distal end.

The distal end 30 of the endoscope 10 may be inserted into a body cavitythrough an anatomic opening in step 130. The increased stiffness of thedistal end of endoscope 10 may assist insertion of endoscope 10 into thebody cavity. For example, in an application of inflatable balloon 40 toa colonoscope (a type of endoscope used for therapeutic procedures onthe colon), increased rigidity of the distal end may allow thecolonoscope to be inserted into the anal cavity through the anus. Theincreased rigidity of the distal end may also allow the colonoscope toadvance through a constricted anal cavity without compressing orkinking. In some embodiments, the endoscope may be inserted in to thebody cavity (step 130) before the inflatable balloon is inflated (step120).

As distal end 30 of endoscope 10 advances through the body cavity, itmay be desirable to reduce the stiffness of distal end 30 to reduce thepossibility of trauma to body tissue. The stiffness of distal end 30 maybe reduced by deflating the inflatable balloon slightly. In someembodiments, an operator may deflate and inflate inflatable balloon 40multiple times to obtain a desired stiffness of the endoscope distal end30. The desired stiffness of distal end 30 may be based on experience ofthe operator and may be a level of inflation that allows endoscope 10 toadvance along the body cavity easily without causing undue trauma to thepatient.

Once distal end 30 advances into a region of the body cavity which isnot constricted, it may be desirable to reduce the rigidity of theregion of endoscope 10 in the unconstricted body cavity further, whilemaintaining the stiffness of the region of endoscope 10 in theconstricted body cavity (step 140). For example, in the application ofthe colonoscope advancing through the anal canal described earlier, oncethe colonoscope is past the anal verge (distal end of the anal canal),it may be desirable to keep the region of the colonoscope past the analverge relatively flexible while maintaining the region of thecolonoscope in the anal canal relatively rigid and inflexible. In someembodiments, it may be desirable to increase the stiffness of one regionof endoscope while decreasing the stiffness of another region. In someembodiments, it may be desirable to deflate the endoscope shaft to makethe shaft soft and/or flexible for easy and non-traumatic removal of theendoscope from the body cavity. In other embodiments it may be desirableto increase the stiffness to a desired level for removal and/orinsertion.

To reduce the stiffness of the distal most region of endoscope 10 whilemaintaining the stiffness of a region ahead of the distal most end (thatis, towards the proximal end), the inflatable balloon 40 may be pulledout of the distal most end using the links coupled to the inflatableballoon 40. In some embodiments, inflatable balloon 40 may be pulled outat about the same rate as endoscope 10 is pushed into the body cavity tokeep the region of the endoscope 10 in the unconstricted body cavityflexible. In an embodiment of inflatable balloon in the form of asegmented balloon (FIG. 3C), balloon segments proximate the distal mostend may be deflated while balloon segments proximal to the distal mostend inflated to move the region of increased stiffness towards theproximal end 20 of endoscope 10 as the endoscope is inserted into thebody cavity.

As indicated earlier, although the invention of the current disclosureis illustrated and described as being applied to an endoscope, theinvention may be broadly applied to any transluminal device. It will beapparent to those skilled in the art that various modifications andvariations can be made in the disclosed systems and processes withoutdeparting from the scope of the invention. Other embodiments of theinvention will be apparent to those skilled in the art fromconsideration of the specification and practice of the inventiondisclosed herein. It is intended that the specification and examples beconsidered as exemplary only, with a true scope of the invention beingindicated by the following claims.

We claim:
 1. A method of using a transluminal device comprising:inserting a distal end of the device into a body cavity, the deviceincluding a lumen extending from a proximal end of the device to thedistal end; positioning a balloon at a first location within the lumen,the first location being a location between the proximal end and thedistal end; and moving the balloon from the first location to a secondlocation in the lumen between the proximal end and the distal end; andinflating the balloon by admitting a fluid therein.
 2. The method ofclaim 1, further including inserting the balloon into the lumen, andwherein the step of inflating the balloon is performed after positioningthe balloon at the first location.
 3. The method of claim 1, wherein thestep of inflating the balloon is performed before positioning theballoon at the first location.
 4. The method of claim 1, furtherincluding deflating the balloon by removing the fluid therefrom, andwherein deflating the balloon increases a flexibility of the device. 5.The method of claim 1, wherein inflating the balloon includes inflatinga first section of the balloon independent of a second section of theballoon by admitting fluid into the first section while not admittingfluid into the second section, the first section and the second sectionsbeing different sections of the balloon, and wherein inflating theballoon decreases a flexibility of the device.
 6. A method of using amedical device comprising: inserting an elongate section of the medicaldevice into a body cavity, the elongate section having a distal end anda proximal end; positioning a balloon at a first location within theelongate section between the proximal end and the distal end; andadjusting a flexibility of the elongate section, wherein the flexibilityof the elongate section is decreased when the balloon is inflated, andthe flexibility is increased when the balloon is deflated.
 7. The methodof claim 6, further including axially moving the balloon between theproximal end and the distal end.
 8. The method of claim 6, wherein theballoon extends substantially from the proximal end to the distal end ofthe elongate section.
 9. The method of claim 6, wherein a length of theballoon is substantially smaller than a length of the elongate section.10. A method of using a medical device comprising: inserting an elongatesection of the medical device into a body cavity, the elongate sectionextending between a proximal end and a distal end of the device, and theelongate section including a first region and a second region betweenthe proximal end and the distal end; and radially expanding a balloonwithin the elongate section to independently adjust the flexibility ofeach of the first region and the second region, wherein: the balloon isconfigured to radially expand from a deflated configuration to aninflated configuration by admitting a fluid therein, and the flexibilityof the first region increases when the balloon is located in the firstregion and expands from the deflated configuration to the inflatedconfiguration.
 11. The method of claim 10, wherein a lumen extendswithin the elongate section from the proximal end to the distal end, andwherein the balloon is disposed within the lumen.
 12. The method ofclaim 10, further comprising a step of moving, using a wire, the balloonfrom the first region to the second region.
 13. The method of claim 10,wherein the balloon extends substantially from the proximal end to thedistal end of the elongate section.
 14. The method of claim 10, whereina length of the balloon is substantially smaller than a length of theelongate section.
 15. The method of claim 10, wherein the balloonincludes multiple segments that are configured to inflate and deflate,wherein the multiple segments are separated by balloon sections that donot substantially inflate and deflate when the fluid is admitted into orremoved from the balloon, and wherein some segments of the multiplesegments are configured to inflate and deflate independently of othersegments.
 16. The method of claim 10, wherein the balloon is fixed inthe device.
 17. The method of claim 10, further including a lumenextending within the elongate section from the proximal end to thedistal end, wherein the balloon is positioned within the lumen andconfigured to be axially movable between the proximal end and the distalend.
 18. The method of claim 10, wherein the balloon extendssubstantially from the proximal end to the distal end of the elongatesection.
 19. The method of claim 10, wherein the balloon is fixed in theelongate section.
 20. The method of claim 10, wherein the deviceincludes a wire configured to move the balloon between a first regionand a second region between the proximal end and the distal end.